By means of a combination of RIA, radioreceptor assay, bioassay, and Heparin-Sepharose (HS) affinity chromatography, the possible presence of FGF in various ocular tissues (retina, cornea, retinal pigmented epithelium, iris, and lens) will be examined. The possible production of FGF by various tumors derived from the eye will be examined. Since ocular tissue would only be sensitive to FGF if specific FGF receptor sites are present, we will also study the presence of FGF receptors in membrane preparations from corneal epithelium or retina. Since the appearance of both FGF and of FGF receptors within ocular tissues could be a developmentally regulated process, we plan to study their appearance in ocular tissues obtained from embryo at different stages of development. the interaction of FGF with cultured endothelial cells and retina-derived capillary endothelial cells will be characterized. Purification of the FGF receptor by affinity chromatography will be attempted. The effect of FGF in vitro on cell migration (an effect particularly important for retinal capillary endothelial cells) and its chemotactic activity on corneal endothelial or retinal capillary endothelial cells will be determined. The effect of FGF on c oncogene activation, which has been shown to be correlated with cell proliferation (c fos and c myc), cell differentiation (c fos), and cell longevity (c ras), will be examined. Since the corneal endothelial cell extracellular matrix (ECM) has been shown to be as potent as FGF in supporting cell proliferation, we will purify from that substrate the factor(s) which could be involved in mediating its mitogenic effect and analyze its relationship with FGF. Since HDL and transferrin have both been shown to be progression factors for cultured corneal endothelial cells, we will delineate their roles in supporting cell survival versus their ability to support cell proliferation.